Question

6.) In the figure, OACB is a
quadrant of a circle with centre
O and radius 3.5cm. If
OD=2cm, find the area of the
shaded region.
(use π= 22/7)
​

Answer 1

Answer:

6.125cm^2

Explanation:

Area of whole quadrant:-

πr^2 / 4

22/7 x 3.5 x 3.5 / 4 = 9.625cm^2

Area of triangle ODB:-

1/2 x b x h

1/2 x 2 x 3.5 = 3.5cm^2

So, area of shaded part = 9.625 - 3.5 = 6.125cm^2

Answer 2

$\huge{\underline{\bigstar{\sf{solution!!}}}}$

Given,OACB is a quadrant of a circle

Radius = 3.5 =7/2 cm; OD= 2cm

$\large{\sf{area\: of \: the \: shaded \: region = area \: of \: a \: quadrant \: cricle - area \:of \: triangle \:BOB}}$

=1/4πr²-1/2×b×h

=1/4×22/7×7/2×7/2-1/2×7/2×2

=11×7/2×2×2 -7/2

[=77/8-7/2

=9.625-3.5

$\large{\boxed{\sf{=6.125cm2}}}$

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